Description of Nocardioides piscis sp. nov., Sphingomonas piscis sp. nov. and Sphingomonas sinipercae sp. nov., isolated from the intestine of fish species Odontobutis interrupta (Korean spotted sleeper) and Siniperca scherzeri (leopard mandarin fish).

A polyphasic taxonomic approach was used to characterize three novel bacterial strains, designated as HDW12A, HDW-15B, and HDW15C, isolated from the intestine of fish species Odontobutis interrupta or Siniperca scherzeri. All isolates were obligate aerobic, non-motile bacteria, and grew optimally at 30°C. Phylogenetic analysis based on 16S rRNA sequences revealed that strain HDW12A was a member of the genus Nocardioides, and closely related to Nocardioides allogilvus CFH 30205 (98.9% sequence identities). Furthermore, strains HDW15B and HDW15C were members of the genus Sphingomonas, and closely related to Sphingomonas lutea JS5 and Sphingomonas sediminicola Dae 20 (97.1% and 97.9% sequence identities), respectively. Strain HDW12A contained MK-8 (H), and strains HDW15B and HDW15C contained Q-10 as the respiratory quinone. Major polar lipid components of strain HDW12A were diphosphatidylglycerol, phosphatidylglycerol, and phosphatidylinositol, and those of strains HDW15B and HDW15C were sphingoglycolipid, diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, and phosphatidylcholine. The G + C content of strains HDW12A, HDW15B, and HDW15C were 69.7, 63.3, and 65.5%, respectively. The results of phylogenetic, phenotypic, chemotaxonomic, and genotypic analyses suggest that strain HDW12A represents a novel species within the genus Nocardioides, and strains HDW15B and HDW15C represent two novel species within the genus Sphingomonas. We propose the names Nocardioides piscis for strain HDW12A (= KACC 21336 = KCTC 49321 = JCM 33670), Sphingomonas piscis for strain HDW15B (= KACC 21341 = KCTC 72588 = JCM 33738), and Sphingomonas sinipercae for strain HDW15C (= KACC 21342 = KCTC 72589 = JCM 33739).